COW SHARK or BROADNOSE SEVENGILL SHARK – Notorynchus cepedianus.
Sevengill cow shark identification: Cow sharks are a primitive form of shark of the order Hexanchiformes, which comprises six species with six or seven paired gill openings (most other sharks have five). The most obvious form of identification is the absence of a first dorsal fin. Of all the Hexanchiformes, the broadnose sevengill cowshark is the species most likely encountered by divers in shallow waters < 50m. The body colouration varies from dark brown to black and grey with mottled white and grey underbelly. The patination of dark and light spots that appear on the body can be used to identify individual sharks. The upper lobe of the caudal fin is almost one third of the total body length.
Broadnose sevengill cow sharks, reach lengths of at least 3 m and weigh over 100 kg. They are thought to reach sexual maturity at 1.5 to 2.2 m in length and are known to live as long as 49 years.